The objective of this project is a detailed analysis of the anatomical interconnections of cortical visual and association areas with the lateral posterior complex of the thalamus. The aim of the analysis is the identification of specific populations of thalamic neurons which are involved in information transfer between visual and association cortex. Autoradiographic methods have been used to demonstrate projections from electrophysiologically identified lateral suprasylvian areas to the lateral posterior complex. Anticipated experiments will employ injection of horseradish peroxidase into electrophysiologically identified cortical areas to identify thalamo-cortical projection patterns.